Alice Jacobus de Moraes

Teores de nutrientes e metais pesados em plantas de estragão submetidas a diferentes fertilizações

The cultivation and use of medicinal plants has accompanied the evolution of mankind since antiquity, together with the development of techniques for their cultivation and management. In the search for sustainability of agroecosystems, the use of sources for fertiliser that provide the necessary nutrients for crops should be handled so as to cause the least possible environmental impact. The aim of this study was to evaluate the availability of N, P, K, Ca, Mg, Cu, Zn, Fe and Mn, and the heavy metals Cd, Pb and Cr, in tarragon plants (Artemisia dracunculus) subjected to different fertilisers, organic (swine-manure based compost) and mineral, in a dystrophic Red Argisol (PVd). The experimental design was completely randomised (DIC) in a 2 x 3 factorial scheme, comprising two sources and three levels of fertilisation (no fertilisation, recommended dose and double the recommended dose), giving a total of six treatments with four replications. The results showed that the source as well as the level of fertiliser influenced availability of the elements under evaluation in the plants. The organic fertilizer provided higher concentrations of Cu and Mn. Mineral fertilisation provided higher levels of the nutrients N and K. The heavy metals Cd and Cr showed no concentrations within the limits of detection for the method used.

Heat shock and salicylic acid on postharvest preservation of organic strawberries

Heat shock and salicylic acid have been studied on shelf-life extension of fruits. The benefits of these techniques have been related to their effect on inducing physiological defense responses against the oxidative stress and pathogen development. The objective of this study was to evaluate the effect of heat shock and salicylic acid on the postharvest preservation and contents of total phenolics, anthocyanins, ascorbic acid, fresh weight loss and microbiological quality of organic strawberries cv. Dover. Strawberries produced organically and stored at 5 °C were subjected to heat shock (45 °C ± 3 °C for 3 h), application of salicylic acid (soaking in 2.0 mmol L -1 solution), heat shock in combination with salicylic acid and control. After treatment, the fruits were packed and stored in a climatic chamber at 5 oC ± 2 oC. At 1, 7 and 14 days, the experimental units were removed from refrigeration and kept at room temperature of approximately 20 oC for two days. There was no effect of treatments on fresh weight loss, incidence of pathogens or chemical variations in strawberry fruits during the storage period. In natural conditions, organically grown strawberries remained in good condition for sale up to seven days of storage in all treatments.